Calculate the difference between Consecutive pair of Elements of a Vector in R Programming – diff() Function

diff() function in R Language is used to find the difference between each consecutive pair of elements of a vector.

Syntax: diff(x, lag, differences)

Parameters:
x: vector or matrix
lag: period between elements
differences: Order of difference

Example 1:

# R program to find the difference
# between each pair of elements of a vector

# Creating a vector
x1 <- c(8, 2, 5, 4, 9, 6, 54, 18)
x2 <- c(1:10)
x3 <- c(-1:-8)

# Calling diff() function
diff(x1)
diff(x2)
diff(x3)

Output:

[1]  -6   3  -1   5  -3  48 -36
[1] 1 1 1 1 1 1 1 1 1
[1] -1 -1 -1 -1 -1 -1 -1

Example 2:

# R program to find the difference
# between each pair of elements of a vector

# Creating a vector
x1 <- c(8, 2, 5, 4, 9, 6, 54, 18)
x2 <- c(1:10)

# Calling diff() function
diff(x1, lag = 2, differences = 1)
diff(x2, lag = 1, differences = 2)

Output:

[1] -3  2  4  2 45 12
[1] 0 0 0 0 0 0 0 0

Here, in the above code, the ‘lag’ tells the period between values, i.e. lag = 2 means, diff is calculated between 1st and 3rd value, 2nd and 4th values, etc. and ‘differences’ tells the order in which diff() function is called i.e. differences = 2 means diff() function is called twice on the vector.